如何限制grails中关联的大小？ [英] How to limit the size of association in grails?

问题描述

  class Order {
 String orderId ='OD'+ System.nanoTime（）。toString（）
 Date orderedDate 
 String itemName 
列出出价; 
 static hasMany = [bid：Bid; likedUsers：User，] 
 static belongsTo = [owner：User] 
} 
 
 class Bid {
 Integer金额
用户bidedUser 
 static belongsTo = [订单] 
} 
类用户{
字符串用户名
字符串密码
字符串emailId 
列出订单
 static hasMany = [订单：订单] 
} 
  

什么我试图做的是，以maxResult为10的位查询订单，就像

  def critObj = Order.createCriteria （）
 critObj.list {
 eq（id，1）
 bids {
 maxResult（10）//试着只抓取10条记录
} 
 
  

如何只加载10位（关联），有可能吗？ 。或者我的领域类的设计是错误的？

解决方案

我认为这应该工作：

  def results = Bid.withCriteria {
 order {
 eq'id'，1 
} 
预测{
 $'$'
 
 
 
 
 $ b $ >但请注意，您必须更改您的出价域类，以便以另一种方式从出价添加关系到订单： 
 
 
  class出价{
 ... 
 static belongsTo = [order：Order] 
} 
  
 
I have a grails domain class as below :
 class Order {
   String orderId = 'OD' + System.nanoTime().toString()
   Date orderedDate
   String itemName
   List bids;
   static hasMany = [ bids: Bid ;likedUsers: User,]
   static belongsTo =[owner:User]
  }

 class Bid {
  Integer amount
  User bidedUser
     static belongsTo = [Order]
  }
   class User {
     String username
     String password
     String emailId
     List orders
     static hasMany = [orders:Order]
     }
What I am trying to do is , to query for an order with bits with maxResult of 10 as like 
 def critObj = Order.createCriteria() 
     critObj.list{
       eq("id" ,1)
       bids {
         maxResult(10) //Trying to fetch only 10 records
        }
    }
How can I load only 10 bits(associations) , is it possible? . Or My design of domain class is wrong?
解决方案
I think this should work:
def results = Bid.withCriteria {
    order {
        eq 'id', 1
    }
    projections {
        property 'order'
    }
    maxResults 10
}
But please note that you have to change your Bid domain class to add the relation in the other way from Bid to Order:
class Bid {
    ...
    static belongsTo = [order: Order]
}


                        
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